Pressure-recorder for air-brakes



(No Model.)

0. A. SGHROYER. PRESSURE RECORDER FOR AIR BRAKES. No. 426,144. Patented Apr. 22, 1890.

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UNITED STATES PATENT OEEIcE.

CHARLES A. SCI'IROYER, OF CHICAGO, ILLINOIS.

PRESSURE-RECORDER FOR AIR-BRAKES.

SPECIFICATION forming part of Letters Patent No. 426,144, dated April 22, 1890.

Application filed October 15, 1889. Serial No. 327,108. (No model.)

To all whom, it may concern.-

Be it known that 1, CHARLES A. SOHROYER, a citizen of the United States, residing in Chicago, Illinois, have invented a new and useful Improvement in Pressure-Recorders for Air-Brakes, of which the following is a specification.

Vith the air-brake system the brakes are applied, as is well known, by means of the Now there is a certain maximum pressure that can be used with advantage,but if this be exceeded there will be danger of spotting or causing unequal wearing of the wheels. The engineer is very apt to use too great pressure in order to make a quick stop, and this causes great loss to the railroads, inasmuch as a spotted Wheel has to be replaced at once. The engineer will of course deny having used a greater pressure than absolutely necessary, and some means of keeping a record of the pressure employed has been sought for. It is therefore the object of my invention to provide a device for preserving a record of the pressure in the air-brake cylinder at each application of the brakes; and the invention consists in the features and details of construction hereinafter described and claimed.

In the drawings, Figure 1 is a front clevation of my device; Fig. 2, a vertical central section taken on the line 2 2 of Fig. 1, look ing in the direction of the arrows; and Fig. 3, a horizontal section on line 3 3 of Fig. 1, also looking in the direction of the arrows.

A is a cylinder or shell; I a screw-cap; B, a piston; b, a piston-rod; O, a plate for at taching the device to a wall or other suit able place and for supporting the recording device; D, a spring inside of the shell A; E, a graduated tape or ribbon; F, a spool or reel for holding the ribbon and off of which the ribbon is wound; F, a similar spool, onto which the ribbon is wound as it passes off of the spool F f a ratchet-wheel attached to the spool F; G, an arm. or bar attached to the upper end of the pistoirrod; II, a pencil or marking-tool secured in such arm; 71., a spring bearing against the outer end of such tool; I, a bar supported in a case or bearing and can rying at one end the ratchet J; 7,3.- spring moving the bar I in one direction; K, a lug upon the arm G bearing against the end of the bar I, and L a spring-catch engaging with the ratchetavheel f.

I first make, preferably of metal and of any suitable dimensions, the cylinder A and supporting-plate C. These may be cast in one piece, or made separately and attached together afterward, as desired. The lower portion of the cylinder is preferably made of less diameter than the upper portion, as shown, the relative dimensions of these two portions depending upon the size of the spring. At the upper end of the cylinder I prefer to provide an adjustable screw-cap. I next make, also preferably of metal, the piston B and its red, the former fitting closely inside of the lower portion of the cylinder A. and the upper end of the piston-rod passing out through the cap B, which thus acts as a guide therefor. This cap is provided with a port or opening P to allow the escape of air. I next provide a spring D of any suitable dimensions. This preferably fits inside of the shell or cylinder A and bears at one end against a collar l), fastened to the piston-rod. The other end of the spring abuts against the inside of the cap B, and the tension of the spring may be varied by screwing this cap up or down upon the shell. I next firmly attach the rod or bar G to the upper end of the piston-rod. This bar is bent, as shown in Fig. 2, and passes down in front of and substantially parallel to the shell A and moves in guides g. Through a slot in this bar I pass a pencil or other suitable marking device, and I prefer to provide a spring 71 for forcing the pencil against the ribbon, as hereinafter set forth. Next 1 construct the spools F and F. These are preferably made of wood, al-

though any other material may be employed, if desired, and are attached securely (but in such manner as to allow of rotation) by means of suitable bolts and nuts to the supportingplate C, as shown more particularly in Fig. 1. iilthough it is not essential, I prefer to use a spring-washer f to hold the spool F steady. The spool F has a ratchet wheelf firmly attached thereto, preferably at the lower end thereof. I then make the rod or barI, carr ing a ratchet .I at one end engaging with the teeth of the ratchet-wheel f. To move this bar in one direction, I prefer to provide the spring 1, bearing against a lug on the bar I,

and to move it in the other direction I preferably provide a lug or projection K upon the bar G. To prevent the spool F turning backward, I also prefer to provide the springhook L. (Shown in Fig. Lastly, I provide the tape or ribbon E. This is made of paper, parchment, or any other suitable material, and of any desired length, and provided with a graduated scale, as shown in Fig. 1, to indicate the pressure. This ribbon is wound upon the spool F and its free end fastened to the spool F, so that the rotation of the latter will wind the ribbon off of the spool F. The ribbon rests against the outside of the cylinder, which is preferably flattened to afford a surface to support the tape while being marked by the pencil. It will of course be understood that while I have only shown one form of scale upon this ribbon, any other may be used, as desired, and that, furthermore, other means maybe employed to rotate these spools, and similar changes may be made in the construction without departing from the spirit of my invention.

The spring is of course to be so graduated that a certain known pressure against the piston 13 shall cause a certain known amount of compression of the spring. \Vhile I have shown this spring as located within the cylinder, I do not consider this essential,inasmuch as the purpose of this spring is to offer a certain definite resistance to the motion of the piston, and it might be located outside of the cylinder and serve this purpose equally well as though inside thereof.

This device is to be connected by apipe or tube with the air-brake cylinder and placed inside of the car or in any other suitable place and as near as possible to the cylinder, in order to avoid reduction of pressure there in. It maybe inclosed in a case provided with a look, so as to be accessible only to the car-inspector or other official. It operates as follows: WVhenever the brakes are applied, the air in the cylinder will press against the piston 13 and foreeit upward against the pressure of the spring. As the piston rises it will carry with it the piston rod, arm, and pencil, and'the latter, bearing against the ribbon, as above set forth, will make a substantially vertical mark thereon, the height of this mark indicating the amount of pressure employed-as, for instance, if there is sixty pounds pressure usedin applying the brakes the vertical mark will extend upward on the ribbon to the line numbered sixty-it being understood, of course, that the scale upon the ribbon is constructed with reference to the amount of ainpressnre required to compress the ribbon a certain distance, the distance the pencil moves corresponding to the distance the spring is compressed. As the bar G rises it carries up with it the lug K, and thereupon the spring '6 carries the bar I, together with its ratchet, toward the left, (see Fig. 1,) thereby allowing the ratchet to engage with another one of the teeth in the ratchet-wheel. Then the brakes are released and the pressure falls, the force of the springD will carry the piston and its red back again to their original position, carrying the bar G along with them. As this bar moves downward, the lug K will again come in contact with the red I and force it to the right, thus partially revolving the spool F and leaving the ribbon in position to record another application of the brakes. Thus it will be seen that upon each application of the brakes a vertical line is made upon the ribbon to a certain height, depending upon the pressure employed, and that upon the brakes being released, and the pressure consequently being taken off, the spool F will be rotated, presenting a fresh part of the paper to the recording-pencil.

I claim-- 1. In a pressure-recorder for air-brakes, the combination of a cylinder, a piston and pi ton-rod, a graduated spring compressed as thepiston is moved by the pressure of the air, a marking-arm attached to the piston-rod, a ribbon or tape upon which the pressure is recorded, spools for holding such tape, and means whereby the spools are rotated by the motion of the marking-arni, substantially as described.

2. In apressureaeeorder for air-brakes, the combination of a cylinder, a piston and piston-rod, a marking-arm. attached to the piston rod provided with a lug, a tape or ribbon for receiving the record of the pressure, spools for holding such tape or ribbon, a ratchetwheel fastened to one of the spools, and a ratchet-arm moved in one direction by a spring and in the other by the lug on the markingarm, whereby the spools are revolved and the tape carried along under the marker, substantially as described.

3. In a pressure-recorder, the combination of a cylinder, a piston and rod, a spring adapted to be compressed as the piston is moved by the pressure of the air, a markingarm attached to the piston-rod, a tape or ribbon upon which the pressure is recorded, and spools upon which said tape or ribbon is wound, such spools remaining stationary while the pressure is recorded, and afterward being automatically revolved by the falling of the piston to present a fresh surface of the tape to the marker, substantially as described.

CHARLES A. SGHROYER.

Erriniirn BANNING, Enonen S. PA vsoN.

ICC 

